Electronic vaping device with pre-heater

ABSTRACT

Provided is an electronic vaping device that includes a heating element configured to convert a portion of a liquid into a vapor by elevating a temperature of the liquid. An airflow passage is defined by the vaping device to channel a stream of a fluid including air, or a combination of air and vapor, adjacent to the heating element as a result of a user inhaling through a mouthpiece. The stream of fluid flowing through the airflow passage entrains the vapor and transports the vapor toward the mouthpiece. A pre-heater is arranged upstream of the heating element to pre-heat at least a portion of the fluid to a pre-heated temperature. The pre-heated temperature is greater than an ambient temperature of the air that is introduced to the pre-heater. A controller independently controls the heating element and the pre-heater.

BACKGROUND OF THE INVENTION 1. Field of the Invention

This application relates generally to a method and apparatus for preheating a fluid that is to entrain a vapor.

2. Description of Related Art

Conventional electronic vaping devices (also commonly referred to as electronic cigarettes or e-cigarettes) typically include a heating element, a power source that supplies energy to energize the heating element, and control electronics to control the supply of energy. A container stores a liquid that is to be delivered to the heating element, where it is vaporized to be inhaled by a user through a mouthpiece.

In an attempt to accurately replicate the sensation of smoking tobacco cigarettes, vaping devices have allowed users to input an operating parameter of the vaping device to match their smoking preferences. Such an operating parameter has traditionally influenced operation of the heating element that converts the liquid into the vapor. However, changing the operation of the heating element offers limited control options to the users. The available options may limit the temperature of the vapor that can be generated, to a temperature that is much lower than the smoke from a traditional tobacco cigarette.

Further, limits to the variable operation of the heating element can also hamper the ability of users to obtain a desired dose of a chemical constituent in the liquid. For example, there may be a cap to the amount of nicotine that can be included in the vapor as a result of varying operation of the heating element. To overcome this, users may resort to altering their use patterns to increase the amount of the vapor inhaled, thereby satisfying their desire for nicotine. However, such changes in usage patterns may still be insufficient to replace, or at least mimic the sensation of smoking a tobacco cigarette, and increases the quantity of the liquid consumed. Consuming excess amounts of the liquid may be costly, and increase the quantities of other chemical constituents of the liquid inhaled by users. Further, increasing the amount of vapor inhaled necessarily requires users to exhale very large clouds of smoke. The large clouds of smoke can be undesirable in certain environments where smaller smoke clouds may go unnoticed, and can be a nuisance to others nearby who have a low tolerance for the exhaled smoke.

BRIEF SUMMARY OF THE INVENTION

According to one aspect, the subject application involves an electronic vaping device that includes a heating element configured to convert a portion of a liquid into a vapor by elevating a temperature of the liquid. The liquid comprises at least a first chemical constituent such as nicotine or a flavor component to be included in the vapor. An airflow passage is defined, and air flows through the airflow passage adjacent to the heating element as a result of a user inhaling through a mouthpiece. The air flows through the airflow passage to entrain the vapor and transport the vapor away from the heating element and toward the mouthpiece. A pre-heater is arranged to heat the air to a pre-heated temperature before the air is introduced to the vapor. The pre-heated temperature is greater than an ambient temperature of the air that is introduced to the pre-heater. A controller independently controls the heating element and the pre-heater.

According to an embodiment, the electronic vaping device can further include a temperature sensor for sensing the pre-heated temperature of the air at an upstream location along the airflow passage, before the air reaches a location where the air is introduced to the vapor. The temperature sensor is operably connected to the controller to transmit the sensed pre-heat temperature to the controller as feedback.

According to an embodiment, the electronic vaping device can further include a vaporizer comprising a power source that supplies electric energy to the heating element, wherein the controller is provided to the vaporizer, and an atomizer that is separable from the vaporizer and comprises a reservoir that stores the liquid in fluid communication with the heating element, wherein the heating element is provided to the atomizer.

According to an embodiment, the pre-heater can include a second heating element that is provided to the vaporizer.

According to an embodiment, the vaporizer can include an air inlet port through which the air is drawn from an ambient environment of the vaporizer to be heated by the second heating element before the heated air, at the pre-heated temperature, is introduced to a portion of the airflow passage defined by the atomizer.

According to an embodiment, the electronic vaping device can further include an airflow sensor forming a portion of the vaporizer.

According to an embodiment, the controller is operable to control a gas fraction of the first chemical constituent included in the vapor independently of at least one of: (i) a mass of the liquid that is converted into the vapor during a puff, and (ii) a temperature of the vapor entrained in the air exiting the mouthpiece.

According to an embodiment, the electronic vaping device can further include a user interface in communication with the controller to receive input from a user and transmit a corresponding signal to the controller. The user interface includes one or more input devices that allow the user to enter at least two user-defined settings selected from a group consisting of: (i) a power setting defining a user-desired quantity of electric power to be supplied to the heating element by a power source, (ii) a temperature setting defining a user-desired temperature of the air entraining the vapor that is to exit the mouthpiece, and (iii) a gas fraction setting defining a user-desired gas fraction of the first chemical constituent in the vapor.

According to an embodiment, the controller is operable to control operation of the heating element and the pre-heater to independently implement each of the user-defined settings.

According to an embodiment, the controller controls operation of the heating element independently of the pre-heater.

According to an embodiment, the pre-heater includes a second heating element, and the second heating element includes as at least one of: (i) a formed wire, (ii) a conductive open-cell foam material, (iii) a foil or a flat plate metal heater, and (iv) a conductive mesh.

According to an embodiment, the second heating element includes the conductive open-cell foam material, and the conductive open-cell foam material is formed from a material selected from the group consisting of: a metal, a metal-alloy, a carbon fiber material, a carbon material, a ceramic material, and a plastic material.

According to an embodiment, the heating element includes a plurality of heat generating structures that are collectively controlled as a group to convert the portion of the liquid into the vapor.

According to an embodiment, the pre-heater includes a plurality of heat generating structures that are collectively controlled as a group to heat the air.

According to an embodiment, the electronic vaping device can further include a user interface in communication with the controller to receive input from a user and transmit a corresponding signal to the controller. The user interface includes an input device that allows the user to enter a user-desired operating temperature of the pre-heater.

According to an embodiment, the electronic vaping device can further include a user interface in communication with the controller to receive input from a user that causes the controller to save information about operation of the vaping device during a puff in a computer-readable medium, and receive an instruction to reproduce the puff using the saved information.

According to an embodiment, the controller is configured to determine a bulk vapor outlet temperature and adjust a temperature of the pre-heater to maintain the bulk vapor outlet temperature in response to changes to a temperature of the heating element.

According to an embodiment, the controller is further configured to adjust a quantity setting defining a quantity of the first chemical constituent in the vapor according to a schedule.

According to an embodiment, the electronic vaping device can further include a sensor that senses a first quality that suggests a puff is imminent and transmits a first signal to the controller. The controller activates the pre-heater before activating the heating element in response to receiving the first signal.

According to an embodiment, the electronic vaping device can further include: a sensor that senses a first quality that suggests a puff is imminent and transmits a first signal to the controller; and a secondary sensor that senses a second quality, different from the first quality, that also suggests the puff is imminent, and transmits a second signal to the controller. The controller activates the pre-heater before activating the heating element in response to receiving both the first signal and the second signal.

The above summary presents a simplified summary in order to provide a basic understanding of some aspects of the systems and/or methods discussed herein. This summary is not an extensive overview of the systems and/or methods discussed herein. It is not intended to identify key/critical elements or to delineate the scope of such systems and/or methods. Its sole purpose is to present some concepts in a simplified form as a prelude to the more detailed description that is presented later.

BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWING

The invention may take physical form in certain parts and arrangement of parts, embodiments of which will be described in detail in this specification and illustrated in the accompanying drawings which form a part hereof and wherein:

FIG. 1 is an exploded view of an illustrative embodiment of a vaping device having a separable atomizer that is capable of being repeatedly removed and re-installed on a vaporizer;

FIG. 2A is a partially-cutaway view of an illustrative embodiment of a vaping device having a separable atomizer that includes at least one vent through which ambient air is drawn into the atomizer and pre-heated before being introduced to the vapor during a puff;

FIG. 2B is a partially-cutaway view of an illustrative embodiment of a vaping device having a vaporizer that includes at least one vent through which ambient air is drawn into the vaporizer and pre-heated before being introduced to the vapor during a puff;

FIG. 2C is a schematic representation of a portion of an atomizer that includes a recycle passage;

FIG. 3 is an illustrative display for adjusting a quantity of a chemical constituent within a vapor; and

FIG. 4 is an illustrative display for adjusting a power level of a heating element.

DETAILED DESCRIPTION OF THE INVENTION

Certain terminology is used herein for convenience only and is not to be taken as a limitation on the present invention. Relative language used herein is best understood with reference to the drawings, in which like numerals are used to identify like or similar items. Further, in the drawings, certain features may be shown in somewhat schematic form.

It is also to be noted that the phrase “at least one of”, if used herein, followed by a plurality of members herein means one of the members, or a combination of more than one of the members. For example, the phrase “at least one of a first widget and a second widget” means in the present application: the first widget, the second widget, or the first widget and the second widget. Likewise, “at least one of a first widget, a second widget and a third widget” means in the present application: the first widget, the second widget, the third widget, the first widget and the second widget, the first widget and the third widget, the second widget and the third widget, or the first widget and the second widget and the third widget.

Accordingly, there is a need in the art for an electronic vaping device that can improve a gas fraction of a chemical constituent of the liquid in the vapor for a given operation of a heating element used to convert a portion of the liquid to the vapor. Such a vaping device can include a pre-heater that pre-heats a stream of air, or a stream of air including previously-entrained vapor, that is to flow adjacent to a generation location where the vapor is generated by the heating element. The preheated stream transports the vapor entrained in the stream as a result of the stream flowing adjacent to the generation location through the mouthpiece to be inhaled by a user. The pre-heater can be controllable independently of the heating element that converts the liquid into the vapor. An inventive user interface can offer the user an ability to input user-defined settings that control at least one, and optionally a plurality of additional parameters of the vaping device, beyond operation of the heating element. Examples of such user-definable settings include at least one of: a power setting for the heating element; a desired vapor temperature setting; and a quantity setting that defines at least one of: a quantity of a chemical constituent desired to be included in the vapor, and a gas fraction of the chemical constituent in the vapor.

With reference to the drawings, FIG. 1 is an exploded view of an embodiment of an electronic vaping device 105. The electronic vaping device 105 includes a vaporizer 120 that is operational to supply electric energy to an atomizer 122, for converting a portion of an e-liquid 124 stored in a reservoir 126 of the atomizer 122 into a vapor. The embodiment of the vaping device 105 in FIG. 1 includes an atomizer 122 that is removable, and capable of being re-installed on the vaporizer 120 or replaced by a compatible replacement atomizer. The atomizer 122 includes a first connector 134 (e.g., a male threaded member in FIG. 1 ) that cooperates with a second connector 136 (e.g., a female threaded receiver in FIG. 1 ) to install the atomizer 122 on the vaporizer 120 in a removable manner, but other releasable/re-installable connectors can be utilized. For the removable embodiments of the atomizer 122, cooperation between the first connector 134 and the second connector 136 can also establish an electrical connection between the vaporizer 120 and the atomizer 122. However, it is to be understood that other embodiments of the vaping device 105 can include a permanent atomizer 122 that is formed as an integral component of the vaporizer 120, and is not removable from the vaporizer 120 without damaging the vaping device 150.

The term “vapor,” as used herein, refers to gaseous molecules of the e-liquid 124 that are evaporated, and small liquid droplets of the e-liquid 124 that are to be suspended or entrained in the air as an aerosol, as a result of being exposed to an elevated temperature of a heating element 206 provided to the atomizer 122. It is the vapor entrained in the air that is inhaled by a user of the vaping device 105 through a mouthpiece 128, which is provided to the atomizer 122 in the embodiment appearing in FIG. 1 .

A partially-cutaway view of an illustrative embodiment of the vaping device 105 is shown in FIG. 2A. According to the illustrated embodiment, the vaping device 105 includes a heating element 206 enclosed within a housing 208 of the atomizer 122. Although referred to herein as a heating element 206 for clarity, it is to be understood that the heating element 206 can include a single heat generating structure such as a coil formed of an electrically-conductive material, for example, or a plurality of heat generating structures. For embodiments of the heating element 206 that include a plurality of heat generating structures, each of the heat generating structures is arranged to elevate the temperature of the liquid, converting at least a portion of the liquid into the vapor. Wicking material 210 can be arranged adjacent to each such heat generating structure of the heating element 206 to convey the liquid to the heat generating structures, and each of the heat generating structures can optionally be controlled together, as a unit. For example, each of the heat generating structures collectively forming the heating element 206 can be electrically connected in parallel with each other. For the sake of brevity and clarity, the heating element 206 is described herein and shown in the drawings as being formed into a coil that encircles a wicking material 210. The wicking material 210 is in fluid communication with the e-fluid 124 in the reservoir 126 defined by the atomizer 122 to convey at least a portion of the e-fluid 124 to the heating element 206 to be converted into the vapor. Alternate embodiments of the atomizer 122 can lack the wicking material 210, instead including one or more channels through which the e-liquid 124 can be delivered to the heating element 206 from the reservoir. Regardless of the presence or absence of the wicking material 210, the heating element 206 is arranged in, or adjacent to an airflow passage 215 through which air entraining the vapor generated by the heating element 206 is inhaled by the user.

A pre-heater 211 is also arranged within the housing 208 of the atomizer 122, adjacent to the airflow passage 215 in FIG. 2A, but upstream along the airflow passage from the heating element 206. Similar to the heating element 206, the pre-heater 211 can include a single heat generating structure such as a coil formed of an electrically-conductive material, for example, or a plurality of heat generating structures. For embodiments of the pre-heater 211 that include a plurality of heat generating structures, each of the heat generating structures is arranged to elevate the temperature of the vapor, which has previously been converted from a liquid form by the heating element 206. Unlike the heating element 206, the air or vapor is transported to the pre-heater 211 through forced convection as a result of the user inhaling through the mouthpiece 128, as opposed to the wicking material 210. Each of the heat generating structures of the pre-heater 211 can optionally be controlled together, as a unit. For example, each of the heat generating structures collectively forming the pre-heater 211 can be electrically connected in parallel with each other. For the sake of brevity and clarity, the pre-heater is described herein and shown in the drawings as being formed into a coil. However, other examples of suitable heat generating structures of the pre-heater 211 include, but are not limited to a resistive heater wire formed into a coil, and a conductive open-cell foam material, a foil and a flat plate metal heater. The conductive open-cell foam material can be formed from a material selected from the group consisting of: a metal; a metal-alloy; a carbon foam material such as that offered under the tradename CFOAM® by CFOAM LLC of Triadelphia, WV for example; a ceramic material; and a plastic material. When a user inhales through the mouthpiece 128, ambient air is drawn into the housing 208 in the directions indicated generally by arrow 214 through one or more air inlet ports, referred to herein as vents 212, formed in the housing 208. The air drawn into the housing 208 through the vent(s) 212 is pre-heated by the pre-heater 211.

Pre-heating the air involves heating the air being drawn into the atomizer 122 to entrain a portion of the vapor being generated by the heating element 206 to a pre-heated temperature, before the pre-heated air entrains the vapor. The pre-heated temperature is greater than an ambient temperature of the air entering the housing 208 through the vents, before that entering air is introduced to the pre-heater 211. The air being pre-heated can be a stream of air drawn from an ambient environment of the vaping device. According to alternate embodiments, the air being pre-heated can include at least a quantity of air drawn from an ambient environment of the vaping device 105 and recycled air comprising a portion of previously-entrained vapor. As shown in the schematic view of the housing 208 in FIG. 2C, the recycled air is returned in a direction indicated generally by arrow 305 through a recycle passage 307. For embodiments including the recycle passage 307, the recycled air can be combined with air drawn through the vent 212 from the ambient environment of the vaping device 105. To clearly describe operation of the pre-heater 211, however, the examples that follow will not utilize recycled air. Once pre-heated, the air can encounter an optional temperature sensor 217 disposed along the airflow path 215 between the pre-heater 211 and the heating element 206. The temperature sensor 217 measures a value indicative of the temperature of the pre-heated air, and transmits a signal as feedback to a controller 224, described below, for effective control of the pre-heater 211. The pre-heated air then travels through the airflow passage 215 over, or at least adjacent to the heating element 206 in the direction indicated generally by arrow 219, and entrains the vapor being generated through operation of the heating element 206. The entrained vapor is then transported through the airflow passage 215 to be inhaled by the user via the mouthpiece 128 in the direction indicated generally by arrow 216. A portion of the entrained vapor can optionally be returned to, and combined with air drawn into the vaping device 105 via a vent 212.

Embodiments of the temperature sensor 217 can also optionally include an airflow sensing capability. According to alternate embodiments, a separate, optional airflow sensor such as sensor 241 in FIG. 2B, for example, can be arranged upstream of the pre-heater 211 to measure the flow rate of air through the airflow passage 225. Being “upstream” of the pre-heater, the airflow sensor 241 is encountered by the air drawn in from the ambient environment before that air reaches the pre-heater 211 during a puff when traveling in the direction indicated by arrow 235. Such a temperature sensor 217 and/or airflow sensor 241 can be disposed within the airflow passage 225 through which the air or the vapor flows during operation of the vaping device 105 as described below. The sensor 217 provided with airflow measurement ability or the airflow sensor 241 of the present embodiment can measure a volume of air introduced to the vapor generated by the heating element 206, a mass flow rate of the air, or any other desired aspect of the airflow. The measured airflow parameter(s) can be transmitted as feedback to the controller 224, allowing the operation of the pre-heater 211 to be further regulated and controlled to account for variations in the airflow parameter.

According to the preceding embodiment, the ambient air is drawn into the atomizer 122, where the air is pre-heated by the pre-heater 211 and the pre-heated air entrains the vapor generated by the heating element 206. An alternate embodiment of a vaping device 105, however, includes a pre-heater 211 and/or temperature sensor 217 provided to the vaporizer 120 as shown in FIG. 2B. Since the atomizer 122 can be misplaced or otherwise disposed of and replaced, incorporating the pre-heater 211 and related circuitry such as the temperature sensor 217, for example, can allow the pre-heater 211 to be used with different atomizers 122. According to the embodiment in FIG. 2B, the atomizer 122 can optionally lack the vent(s) 212, or can include the vent(s) 212 to allow for a greater range of adjustment of the mass or volumetric flow rate of the airflow than could be achieved without the vent(s) 212. For the sake of discussion, the embodiment of the atomizer 122 in FIG. 2B is devoid of the vent(s) 212.

The vaporizer 120 in the embodiments of FIGS. 2A and 2B includes a housing 218 that encloses a power supply 220 such as a battery or battery bank that stores the electric energy used to energize the heating element 206. Examples of the power supply 220 include, but are not limited to a rechargeable, Lithium-ion battery, for example. A user interface 222 is exposed at a surface of the vaporizer 120 to allow the user to input one or more operational parameters to be established by a controller 224 to generate the vapor during each puff. Each individual process involving activation of the heating element 206 and inhalation of the vapor generated by the activated heating element 206 is referred to herein as a “puff.”

For the embodiment shown in FIG. 2B, the housing 218 of the vaporizer 120 includes one or a plurality of vents 221. Similar to the vent(s) 212, the vent(s) 221 form one or more inlet ports in the housing 218 through which ambient air can be drawn, in the direction indicated by arrow 235, into the vaporizer 120 to be pre-heated by the pre-heater 211 before being introduced to the vapor generated by the heating element 206. Once pre-heated, the air can encounter the optional temperature sensor 217 disposed within the vaporizer 120 along the airflow path 215 between the pre-heater 211 and the heater 206. The temperature sensor 217 measures a value indicative of the temperature of the pre-heated air, and transmits a signal as feedback to the controller 224, described below, for effective control of the pre-heater 211. The pre-heated air then travels through the airflow passage 225 in the direction indicated generally by arrow 227, toward the atomizer 122. The pre-heated air can optionally enter the atomizer 122 through the cooperating connectors 134, 136 (FIG. 1 ). From there, the pre-heated air then passes over, or at least adjacent to the heating element 206 in the direction as described for the embodiment including the preheater 211 provided to the atomizer 122.

The user interface 222 includes a fire button 226 that, when pressed, causes the controller 224 to close a switch 228 (e.g., a relay, power transistor, etc.) or otherwise electrically connect the power supply 220 to the heating element 206, thereby energizing the heating element 206 to generate the vapor for the puff. Pressing the fire button 226 also results in the controller 224 controlling the switch 228 to electrically connect the power supply 220 to the pre-heater 211. Examples of the controller 224 can include a computer processor (e.g., microprocessor comprising one or a plurality of processing cores) programmed with computer-executable instructions, an application specific integrated circuit (“ASIC”) configured to perform the processes described herein, a circuit comprised of interconnected circuitry components, and the like. According to alternate embodiments, the fire button 226 can be replaced by a control routine programmed into the controller 224 that automatically activates the heating element 206 in response to detecting a negative pressure or the flow of air through the atomizer 122 caused by the user. The controller 224 can control activation of the heating element 206 via the switch 228 independently of the pre-heater 211, and vice versa, according to any suitable power modulation protocol such as pulse-width modulation, variable DC-DC conversion. Operation of the switch 228 by the controller 224 can optionally be based on feedback corresponding to the temperature sensed by the temperature sensor 217. Thus, the controller 224 can supply independent quantities of electric power to the heating element 206 and the pre-heater 211.

It is desirable to get the heating element 206 and the pre-heater 211 up to operating temperature as quickly as possible once a puff starts. To do this, an elevated initial peak power can be supplied to the heating element 206 and the pre-heater 211, and the elevated initial peak power can be higher than the typical operating power of the heating element 206 and the pre-heater 211 while the vaping device 105 is generating the vapor during the puff. The elevated initial peak power is a significant drain on the power supply 220, which can be addressed by increasing the size of the power supply 220 which, in turn, requires a large housing 218. To avoid the undesirable increase in the housing 218 size, yet still activate the pre-heater 211 prior to the actual start of the puff, a sensor can be provided at one or more locations of the vaping device 105 likely to be contacted by the user, or at least be positioned adjacent to the user during the time leading up to a puff. For example, a sensor 245 (FIG. 2B) that is responsive to touch, the proximity of a part of the user, or reflectance of light, for example, can optionally be provided adjacent to the fire button 226. As the user prepares to press the fire button 226, the sensor 245 can transmit a signal to the controller 224 that causes the controller to activate the pre-heater 211 before the fire button 226 is pressed. According to another embodiment, a sensor 247 can be arranged on, or adjacent to the mouthpiece 128. The sensor 247 can be touch sensitive, reactive to the proximity of the user's lips or other anatomical feature approaching the mouthpiece 128, or responsive to any other condition that would indicate the imminent onset of a puff. Regardless of the nature of the sensor, the controller 224 can activate the pre-heater 211 before the puff begins (e.g., before the fire button 226 is pressed or the user inhaling through the mouthpiece is sensed) and before the heating element 206 is activated for the puff. The pre-heater 211 can then begin to get up to operating temperature before the heating element 206 that converts the liquid 124 into the vapor is activated.

According to an alternate embodiment, the above sensor can be provide to the vaping device 105 in combination with a secondary sensor 249 (FIG. 2B) such as an accelerometer, motion sensor, etc., that senses a gesture by the user and/or an orientation of the vaping device 105. The sensed gesture and/or orientation suggests the user is picking up the vaping device 105 to perform a puff, and causes the sensor 249 to transmit a secondary signal to the controller 224. The controller 224 can activate the pre-heater 211 based on the secondary signal alone to begin getting the pre-heater 211 up to temperature before the heating element 206 that generates the vapor is activated, or can activate the pre-heater 211 early in response to receiving the signal from one or both of the sensors 245, 247 above and the secondary signal. Requiring receipt of the second signal in addition to at least one of the other signals would help to avoid false activations of the pre-heater 211 that might otherwise happen if only one signal was required.

The user interface 222 can also include one or a plurality of selectors 230 such as tactile or membrane buttons, a touch screen interface, etc., to allow the user to specify one or a plurality of user-defined settings of the vaping device 105. For example, the selectors 230 can be manipulated by the user to enter at least one, or at least two of the user-defined settings such as: (i) a power setting defining a user-desired quantity of electric power to be supplied to the heating element 206 by a power source to generate the vapor, (ii) a power setting defining a user-desired temperature of the pre-heater 211, (iii) a temperature setting defining a user-desired temperature of the vapor entrained in the air that is to exit the mouthpiece 128, and (iii) a gas fraction setting defining a user-desired gas fraction of the first chemical constituent to be included in the vapor.

Due to the limited space available on the vaporizer 120, a display device 232 such as a color LCD display, for example, can be configurable into a first mode for adjusting a user-defined setting, and a second mode to convey information about the operation of the vaping device 105. As shown in FIG. 3 , a temperature input mode of the display device 232 displays a scale 237 from low to high. The user can manipulate one of the selectors 230 to increase the desired temperature of the vapor, the operating temperature of the heating element 206, the operating temperature of the pre-heater 211, or any other temperature-sensitive component, causing the number of solid blocks to increase. In this manner, an intuitive user interface can allow for relative adjustment of the temperature (e.g., hotter or cooler) to be specified as the temperature setting.

To place the display device 232 in the power selection mode shown in FIG. 4 , both selectors 230 can be pressed concurrently, or any other procedure performed to cycle to the next mode. In the power selection mode, the user can increase and decrease a graphical representation of the setting, a numerical value 239 representing the quantity of electric power to supply to the heating element 206, or any other power-sensitive setting. The numerical value can represent a power level (e.g., a number of Watts) or be a number selected within a range of values to input a relative power level (e.g., on a scale from 1-lowest power to 20-highest power). The volume of vapor produced is related to the power setting, so the power setting can be considered to be a volume setting. Again, use of the relative setting values can provide a user intuitive control mechanism instead of requiring users to expressly enter the desired power value, in Watts, and understand the relationship such a value has on the operation of the heating element 206. A similar, graphical display can be utilized to allow the user to specify any desired setting of the vaping device 105.

Another embodiment of the user interface 222 is configured such that one or more of the selectors 230 can be manipulated by a user to record and save, in the computer-readable medium 202, information for a puff. The information can include at least one of: (i) a power or temperature setting for the heating element 206, (ii) a power or temperature setting for the pre-heater 211, and (iii) a relationship between the electrical resistance of the heating element 206 and time during a puff. This saved information can be assigned a designation (e.g., pre-set number, etc.) that a user can quickly recall to reproduce the puff during which the information was recorded and saved. A pre-defined number of such “favorites” can be saved in the computer-readable medium, and recalled to replay the corresponding puffs through appropriate manipulation of the selector(s) 230.

The user-defined settings can be stored in a non-transitory computer-readable medium 202 provided to the vaporizer 120. The computer-readable medium 202 can be in communication with the controller 224, and store algorithms based on models for implementing the user-defined settings. For example, when the fire button 226 is pressed or the heating element 206 is to be activated for a puff in response to sensing the user inhaling through the mouthpiece 128, the controller 224 can process the user-defined settings based on the algorithms stored by the computer-readable medium 202. Based on a processing result, the controller 224 can independently control activation of the heating element 206 and the pre-heater 211 to implement the user-defined power of the heating element 206, to produce the user-specified quantity of the vapor, within a reasonable error (e.g., ±10%, ±20%, etc.). For other embodiments, the controller 224 can independently control activation of the heating element 206 and the pre-heater 211 based on the user-defined temperature setting, to produce a gas fraction of a chemical constituent or an overall gas fraction of the vapor corresponding to the user-specified temperature setting. The control algorithms can be based on a feed-forward control model for user defined settings that are not established based on feedback. For example, the user-defined temperature of the combined vapor/air exiting the mouthpiece 128 may not be sensed downstream of the heating element 206. Accordingly, the feed-forward control model is independent of any sensed temperature at the outlet of the mouthpiece 128, and based on models stored in the computer-readable medium. Since the user-defined settings are relative, a user can simply increase the temperature setting, for example, in the event the gas fraction of the chemical constituent in the vapor exiting the mouthpiece 128 is not to the user's liking.

In use, the vaping device 105 of FIG. 2B receives the user-defined power setting, temperature setting or other setting input via the selectors 230. The received input can be stored in the computer-readable medium 202. In response to receiving a puff command when the user presses the fire button 226 or inhales through the mouthpiece 128, the controller 224 initiates a puff. To initiate the puff, the controller 224 independently controls operation of the heating element 206 and the pre-heater 211 based on the control algorithms stored in the computer-readable medium 202 and the user-defined settings. As the user inhales through the mouthpiece 128 during the puff, the air is drawn into the housing 218 of the vaporizer 120 toward the pre-heater 211. The flow rate of the air drawn into the housing 218 can optionally be measured by the airflow sensor 241. At the pre-heater 211, the air is pre-heated to a suitable pre-heat temperature defined by the control algorithm. The suitable pre-heat temperature is determined by the control algorithm to be a temperature of the pre-heater 211 such that the air, entraining the vapor generated by the heating element 206 at the exit of the mouthpiece 128, has the user-defined temperature and, accordingly, a desired gas fraction of a chemical constituent in the vapor. Feedback from the sensor 217 (e.g., measured temperature and/or mass flow rate of the pre-heated air flowing over the heating element 206) can further refine the control of the pre-heater 211, in real time.

As another specific example, the user can manipulate a selector 230 to input a desired output temperature of the vapor or a desired pre-heater 211 temperature. A vaping device 105 that includes only the heating element 206 that converts the liquid into a vapor (i.e., that lacks a pre-heater 211) allows users adjust the power setting to a plurality of successively lower power levels. Each lower power level decreases the output temperature of the vapor because the heating element 206 that generates the vapor is the only device that adds energy to the liquid. By including the pre-heater 211, users can elect to input a relatively low power level for the heating element 206 to decrease the quantity of the vapor produced and, in turn, decrease the quantity of nicotine or other chemical constituent inhaled by the user through the mouthpiece. Decreasing the quantity of nicotine is one aim of a smoking cessation program. However, users can compensate for the decrease in vapor temperature that would otherwise result by inputting an increased pre-heater temperature setting using a selector 230. As a result, the controller 224 increases the amount of energy added to the air that is to entrain the vapor by pre-heater 211, producing an output vapor at a temperature comparable to, or approximately the same as the output vapor temperature that would be established by a vaping device having only the heating element 206 at a relatively-high power setting. Keeping the output vapor temperature the same helps to keep the user experience consistent, while automatically (e.g., according to a schedule implemented by the controller 224) or manually (e.g., through manual manipulation of a selector 230) stepping down nicotine consumption down over time.

Through independent control of the heating element 206 and pre-heater 211, based on the user-defined settings, properties of the vapor can be achieved that would not be possible by controlling only the temperature of the heating element 206. For example, at least two of the quantity of the vapor, the temperature of the vapor generated by the heating element 206, and the gas fraction of a constituent in the vapor can be independently controlled (e.g., vary one property without varying at least one other property).

Illustrative embodiments have been described, hereinabove. It will be apparent to those skilled in the art that the above devices and methods may incorporate changes and modifications without departing from the general scope of this invention. It is intended to include all such modifications and alterations within the scope of the present invention. Furthermore, to the extent that the term “includes” is used in either the detailed description or the claims, such term is intended to be inclusive in a manner similar to the term “comprising” as “comprising” is interpreted when employed as a transitional word in a claim. 

What is claimed is:
 1. An electronic vaping device comprising: a heating element configured to convert a portion of a liquid into a vapor by elevating a temperature of the liquid, wherein the liquid comprises at least a first chemical constituent to be included in the vapor; an airflow passage through which air flows adjacent to the heating element as a result of a user inhaling through a mouthpiece, wherein the air flows through the airflow passage to entrain the vapor and transport the vapor away from the heating element and toward the mouthpiece; a pre-heater arranged to pre-heat the air to a pre-heated temperature as the air is being drawn toward a location where the air is to be introduced to the vapor, wherein the pre-heated temperature is greater than an ambient temperature of the air that is introduced to the pre-heater; and a controller that independently controls the heating element and the pre-heater.
 2. The electronic vaping device of claim 1 further comprising a temperature sensor for sensing the pre-heated temperature of the air at an upstream location along the airflow passage, before the air reaches a location where the air is introduced to the vapor, wherein the temperature sensor is operably connected to the controller to transmit the sensed pre-heat temperature to the controller as feedback.
 3. The electronic vaping device of claim 1 further comprising: a vaporizer comprising a power source that supplies electric energy to the heating element, wherein the controller is provided to the vaporizer, and an atomizer that is separable from the vaporizer and comprises a reservoir that stores the liquid in fluid communication with the heating element, wherein the heating element is provided to the atomizer.
 4. The electronic vaping device of claim 3, wherein the pre-heater comprises a second heating element that is provided to the vaporizer.
 5. The electronic vaping device of claim 4, wherein the vaporizer comprises an air inlet port through which the air is drawn from an ambient environment of the vaporizer to be heated by the second heating element before the heated air, at the pre-heated temperature, is introduced to a portion of the airflow passage defined by the atomizer.
 6. The electronic vaping device of claim 3 further comprising an airflow sensor forming a portion of the vaporizer.
 7. The electronic vaping device of claim 1, wherein the controller is operable to control a gas fraction of the first chemical constituent included in the vapor independently of at least one of: (i) a mass of the liquid that is converted into the vapor during a puff, and (ii) a temperature of the vapor entrained in the air exiting the mouthpiece.
 8. The electronic vaping device of claim 1 further comprising a user interface in communication with the controller to receive input from a user and transmit a corresponding signal to the controller, wherein the user interface comprises one or more input devices that allow the user to enter at least two user-defined settings selected from a group consisting of: (i) a power setting defining a user-desired quantity of electric power to be supplied to the heating element by a power source, (ii) a temperature setting defining a user-desired temperature of the air entraining the vapor that is to exit the mouthpiece, and (iii) a gas fraction setting defining a user-desired gas fraction of the first chemical constituent in the vapor.
 9. The electronic vaping device of claim 8, wherein the controller is operable to control operation of the heating element and the pre-heater to independently implement each of the user-defined settings.
 10. The electronic vaping device of claim 9, wherein the controller controls operation of the heating element independently of the pre-heater.
 11. The electronic vaping device of claim 1, wherein the pre-heater comprises a second heating element, and wherein the second heating element comprises as at least one of: (i) a formed wire, (ii) a conductive open-cell foam material, (iii) a foil or a flat plate metal heater, and (iv) a conductive mesh.
 12. The electronic vaping device of claim 11, wherein the second heating element comprises the conductive open-cell foam material, and the conductive open-cell foam material is formed from a material selected from the group consisting of: a metal, a metal-alloy, a carbon fiber material, a carbon material, a ceramic material, and a plastic material.
 13. The electronic vaping device of claim 1, wherein the heating element comprises a plurality of heat generating structures that are collectively controlled as a group to convert the portion of the liquid into the vapor.
 14. The electronic vaping device of claim 1, wherein the pre-heater comprises a plurality of heat generating structures that are collectively controlled as a group to heat the air.
 15. The electronic vaping device of claim 1 further comprising a user interface in communication with the controller to receive input from a user and transmit a corresponding signal to the controller, wherein the user interface comprises an input device that allows the user to enter a user-desired operating temperature of the pre-heater.
 16. The electronic vaping device of claim 1 further comprising a user interface in communication with the controller to receive input from a user that causes the controller to save information about operation of the vaping device during a puff in a computer-readable medium, and receive an instruction to reproduce the puff using the saved information.
 17. The electronic vaping device of claim 1, wherein the controller is configured to determine a bulk vapor outlet temperature and adjust a temperature of the pre-heater to maintain the bulk vapor outlet temperature in response to changes to a temperature of the heating element.
 18. The electronic vaping device of claim 17, wherein the controller is further configured to adjust a quantity setting defining a quantity of the first chemical constituent in the vapor according to a schedule.
 19. The electronic vaping device of claim 1 further comprising a sensor that senses a first quality that suggests a puff is imminent and transmits a first signal to the controller, wherein the controller activates the pre-heater before activating the heating element in response to receiving the first signal.
 20. The electronic vaping device of claim 1 further comprising: a sensor that senses a first quality that suggests a puff is imminent and transmits a first signal to the controller; and a secondary sensor that senses a second quality, different from the first quality, that also suggests the puff is imminent, and transmits a second signal to the controller, wherein the controller activates the pre-heater before activating the heating element in response to receiving both the first signal and the second signal. 